linux-kernel - Re: [GIT PULL 11/14 for v6.17] vfs integrity

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <CAHk-=wh2KaNHTs-gUa227ssG-pE8NMsaz3bg=asx--ntVJaqJg@mail.gmail.com>
Date: Tue, 29 Jul 2025 01:39:45 -0700
From: Linus Torvalds <torvalds@...ux-foundation.org>
To: Christoph Hellwig <hch@...radead.org>
Cc: Hugh Dickins <hughd@...gle.com>, Christian Brauner <brauner@...nel.org>, 
	Klara Modin <klarasmodin@...il.com>, Arnd Bergmann <arnd@...db.de>, Anuj Gupta <anuj20.g@...sung.com>, 
	linux-fsdevel@...r.kernel.org, linux-kernel@...r.kernel.org
Subject: Re: [GIT PULL 11/14 for v6.17] vfs integrity

On Tue, 29 Jul 2025 at 00:49, Christoph Hellwig <hch@...radead.org> wrote:
>
> I don't think overrides are intentional here.  The problem is that
> Christian asked for the flexible size growing decoding here, which
> makes it impossible to use the simple and proven ioctl dispatch by
> just using another case statement in the switch.

Right. Which is why I put it in the default: branch.

IOW, just handle the important real and normal cases first - the ones
that *can* be handled with simple switch statements.

So putting it at the *top*, and then saying "if it returns this
special error code that isn't standardized we do the normal ones" is
wrong.

It's wrong because we literally have over half a century of confusion
about error codes in this area, predating Linux.

And it's also wrong because that new ioctl simply shouldn't be
prioritized over existing ones.

So I'm just saying "don't do that then".

               Linus